2 - Raspberry PI Community Projects

6.8.2. Configuring APT
The case of APT is simple: the -y option (or --assume-yes) tells APT to consider the answer to
all its questions to be “yes”.
6.8.3. Configuring debconf
The case of debconf deserves more details. This program was, from its inception, designed to
control the relevance and volume of questions displayed to the user, as well as the way they are
shown. That is why its configuration requests a minimal priority for questions; only questions
above the minimal priority are displayed. debconf assumes the default answer (defined by the
package maintainer) for questions which it decided to skip.
The other relevant configuration element is the interface used by the front-end. If you choose
noninteractive out of the choices, all user interaction is disabled. If a package tries to display
an informative note, it will be sent to the administrator by email.
To reconfigure debconf, use the dpkg-reconfigure tool from the debconf package; the relevant
command is dpkg-reconfigure debconf. Note that the configured values can be temporarily
overridden with environment variables when needed (for instance, DEBIAN_FRONTEND controls
the interface, as documented in the debconf(7) manual page).
6.8.4. Handling Command Line Interactions
The last source of interactions, and the hardest to get rid of, is the configuration scripts run
by dpkg. There is unfortunately no standard solution, and no answer is overwhelmingly better
than another.
The common approach is to suppress the standard input by redirecting the empty content of
/dev/null into it with command